Existing optical-fiber arrays are generally difficult to manufacture because of the required alignment precision between fibers. Many conventional fiber-array systems, like V-groove-based substrates that hold an array of fibers, also have limited power-handling capability. In addition, for applications such as spectral-beam combining, existing optical-fiber arrays present excessive optical aberrations from their extended source of light.
U.S. Pat. No. 7,058,275 (hereinafter, “Sezerman et al.”), titled “STRESS RELIEF IN FIBRE OPTIC ARRAYS”, issued Jun. 6, 2006, and is incorporated herein by reference. Sezerman et al. describe a mechanism for achieving symmetrical stress loads on operating optical fibers held in fiber-optic arrays that includes, in one embodiment, the provision of a pair of non-operating or dummy fibers, each located outboard of the outermost or curb fibers of the array. All of the fibers, whether operating or dummy, are held in corresponding grooves in a substrate.
U.S. Pat. No. 6,402,390 (hereinafter, “Anderson et al.”), titled “V-GROOVE ADAPTERS FOR INTERCONNECTING OPTICAL CONDUCTORS”, issued Jun. 11, 2002, and is incorporated herein by reference. Anderson et al. describe a V-groove adapter for interconnecting optical conductors that includes V-grooves that are precisely aligned with respect to one another to provide a desired alignment of the respective cores of the optical conductors received within the respective V-grooves.
U.S. Pat. No. 7,738,751 (hereinafter, “Minden et al.”), titled “ALL-FIBER LASER COUPLER WITH HIGH STABILITY”, issued Jun. 15, 2010, and is incorporated herein by reference. Minden et al. describe a plurality of optical fibers arranged in a close-packed hexagonal array having 1+3n(n+1) fibers with (3/2)(n2−n)+3 interferometrically dark fibers and (3/2)(n2+3n)−2 light fibers, where n is an integer greater than or equal to 1. Each optical fiber has a first end and a second end. The plurality of optical fibers are fused together along a section of each optical fiber proximate the first end of each optical fiber to form a fused section having a fiber axis. The fused section of the plurality of optical fibers is tapered to form a tapered region. A facet is at an end of the fused section. The facet is disposed in a direction perpendicular to the fiber axis.
U.S. Pat. No. 5,907,436 titled “Multilayer dielectric diffraction gratings” issued May 25, 1999 to Perry et al., and is incorporated herein by reference. This patent describes the design and fabrication of dielectric grating structures with high diffraction efficiency. The gratings have a multilayer structure of alternating index dielectric materials, with a grating structure on top of the multilayer, and obtain a diffraction grating of adjustable efficiency, and variable optical bandwidth.
Other patents that can be used with or in the present invention include U.S. Pat. No. 6,172,812 (hereinafter, “Haaland et al.”), titled “ANTI-REFLECTION COATINGS AND COATED ARTICLES”, issued Jan. 9, 2001; U.S. Pat. No. 6,406,197 (hereinafter, “Okuda et al.”), titled “OPTICAL FIBER COUPLER, A PROCESS FOR FABRICATING THE SAME AND AN OPTICAL AMPLIFIER USING THE SAME”, issued Jun. 18, 2002; U.S. Pat. No. 6,178,779 (hereinafter, “Drouart et al.”), titled “BUTT WELDING OPTICAL FIBER PREFORMS WITH A PLASMA TORCH”, issued Jan. 30, 2001; U.S. Pat. No. 7,416,347 (hereinafter, “Livingston et al.”), titled “OPTICAL FIBER ARRAY CONNECTIVITY SYSTEM WITH INDICIA TO FACILITATE CONNECTIVITY IN FOUR ORIENTATIONS FOR DUAL FUNCTIONALITY”, issued Aug. 26, 2008; U.S. Pat. No. 7,707,541 (hereinafter, “Abrams et al.”), titled “SYSTEMS, MASKS, AND METHODS FOR PHOTOLITHOGRAPHY”, issued Apr. 27, 2010; U.S. Pat. No. 6,614,965 (hereinafter, “Yin”), titled “EFFICIENT COUPLING OF OPTICAL FIBER TO OPTICAL COMPONENT”, issued Sep. 2, 2003; U.S. Pat. No. 7,128,943 (hereinafter, “Djeu”), titled “METHODS FOR FABRICATING LENSES AT THE END OF OPTICAL FIBERS IN THE FAR FIELD OF THE FIBER APERTURE”, issued Oct. 31, 2006; U.S. Pat. No. 3,728,117 (hereinafter, “Heidenhain et al.”), titled “OPTICAL DIFFRACTION GRID”, issued Apr. 17, 1973; U.S. Pat. No. 4,895,790 (hereinafter, “Swanson et al.”), titled “HIGH-EFFICIENCY, MULTILEVEL, DIFFRACTIVE OPTICAL ELEMENTS”, issued Jan. 23, 1990; U.S. Pat. No. 6,822,796 (hereinafter, “Takada et al.”), titled “DIFFRACTIVE OPTICAL ELEMENT”, issued Nov. 23, 2004; U.S. Pat. No. 6,958,859 (hereinafter, “Hoose et al.”), titled “GRATING DEVICE WITH HIGH DIFFRACTION EFFICIENCY”, issued Oct. 25, 2005; U.S. Pat. No. 7,680,170 (hereinafter, “Hu et al.”), titled “COUPLING DEVICES AND METHODS FOR STACKED LASER EMITTER ARRAYS”, issued Mar. 16, 2010; which are each incorporated herein by reference. Each of these references describes optical systems and/or components that can be combined with and/or used in various embodiments of the present invention.
There is a need for an improved optical-fiber array method and apparatus, particularly optical-fiber arrays having improved power handling and functionality.